The primary objective of this study is to evaluate the utility of the Banyan UCH-L1/GFAP Detection Assay as an aid in the evaluation of suspected traumatic brain injury (Glasgow Coma Scale score 9-15) in conjunction with other clinical information within 12 hours of injury to assist in determining the need for a CT scan of the head.

Inclusion Criteria:

• subject is at least 18 years of age at screening
• suspected traumatically induced head injury as a result of insult to the head from external force
• GCS 9-15 at time of informed consent
• workup includes head CT scan as part of clinical emergency care within 3 hours of presenting and within 12 hours of injury
• blood sample collected within 3 hours of presenting and within 12 hours of injury
• subject or legal representative is willing to undergo informed consent

Exclusion Criteria:

• participating in an interventional, therapeutic clinical study that may affect the results of this study (an observational study acceptable)
• time of injury cannot be determined
• primary diagnosis of ischemic or hemorrhagic stroke
• venipuncture not feasible
• a condition precluding entry into the CT scanner
• subject has a neurodegenerative disease or other neurological disorder including dementia, Parkinson's disease, multiple sclerosis, seizure disorder, brain tumors, and history of neurosurgery, stroke or TIA within the last 30 days
• administration of blood transfusion after head injury and prior to study blood draw
• subject is otherwise determined by the Investigator to be unsuitable for participation

Subjects eligible for study participation will be over the age of 18 and present to the health care facility with a head injury at a time such that sample collection can be completed within 12 hours of injury. Subjects who will be permitted into the study include those who will meet all the inclusion criteria and will have none of the exclusion criteria.